Drill steel retainer



June 4, 1935. c, cums 2,003,924

DRILL STEEL RETAINER Fiied July 15, 1932 JOHN c. cu/er/a '4 I I 53?.Wq

ATTORNEY Patented June 4, 1935 UNITED STATES DRILL STEEL RETAINER John 0. Curtis, Cleveland, Ohio, assignor to The Cleveland Rock Drill Company, Cleveland; Ohio, a corporation of Ohio Application July 13, 1932, Serial N6. 622,222

7 Claims. (o1. 121 s2) This invention relates broadly to rock drills of the percussion type and more particularly to improvements in drill steel retainer.

One of the objects of this invention is to produce a releasable drill steel or tool retainer which is simple in design, economic in manufacture, and susceptible of ready manipulation.

Another object is to provide a tool retainer which is organized to prevent the accidental dis- 1( engagement of the tool from the drill.

' Another object is to provide a rock drill with a tool retainer wherein the cutting tool may be introduced within the machine regardless of the position of the retainer, thus-facilitating the operation of the mechanism.

Other objects and advantages more or less ancillary to the foregoing and the manner in which the various objects are attained reside in the specific construction and aggroupment of the 0 elements peculiar to this structure, as will become apparent from a more complete examination of this specification, in the claims of which there are assembled certain specific combinations of parts and specific constructions indicative of the scope and spirit of the invention.

In the drawing which illustrates a preferred embodiment of the invention? Fig. l is an elevational view partly in section of the front end of a rock drill illustrating the drill steel retainer in an operative or closed position.

Fig. 2 is a cross sectional view taken in a plane indicated by line 2-2 in Fig. 3 illustrating the retainer in an inoperative position.

35 Fig. 3 is an elevational view partly in section taken at right angle to Fig. 1.

Fig. 4 is an end view of the retainer positioned as illustrated in Fig. 2.

Fig. 5 is an end view of the retainer positioned I; as illustrated in Fig. 1.

Referring to the drawing, in which like symbols designate corresponding parts throughout the several views, there is shown a front head I I) which forms the lower portion. of a rock 2 drill. The front head is manufactured with an hexagonal bore I I within which there is slidably mounted the shank I2 of a cutting tool I3, upon which the working piston of the rock drill is capable. of delivering its blow. The length of 50 the shank I2 is limited by a collar I4 formed integral therewith and slidably mountedwithin a cylindrical counterbore I5, locatedin axial alignment with the bore I I and opening from the'forward end of the front head I0. 7

5 The external walls of the counterbore I5 are formed with two diametrically opposed flats I6 terminated toward the front by'projecting ribs I'I disposed in angular relation with the center axis of the machine. Uniting the-flats I6, there is provided. through the wall of the housing I0 5 an aperture I8. The portion of each of the flats I 6 circumventingthe aperture I8 are counterbored as at I9. Through the wall of the housing I0, diametrically opposed to the aperture I8 there is provided a slot 20, forming two side 10 walls 2I and 22. The slot is of sufficient depth to open within the counterbore I5, the purpose of which will be explained later.

Rotatably mounted within the aperture I8, there is a shaft 23 formed intermediate its ends 15 with an annular recess 24 within which there is engaged a pin 25 which is slidably disposed within a bore 26:, and maintained in engagement with the shaft 23 by a tension of a compression spring 21; which is interposed between the bottom of the bore 26 and pin 25. Within the recess 24, the shaft 23 is provided with a transversely disposed orifice 28.

Pivotally mounted upon the ends of the shaft 23, there is a tool retainer 29 comprising a yoke 25 formed with a throat 30, having arms 3| and 32 extending therefrom in straddled relation with the housing I0. These arms are conveniently spaced from each other to allow the passage thereof over the diametrically opposed flats I9. Toward their outer end, the arms 3I and 32 are formed with an enlarged head 33 rotatably mounted within the counterbore I9. The heads 33 are provided with a transversely disposed orifice 34' capable to receive the ends of the shaft 23. Extending upwardly from one of the heads 33, there is an integral handle 35 maintained in spaced relation with the housing Ill, by the engagement of the arms 3| and 32 with the ribs I1, and the engagementof yoke throat 30 with the lower wall 22 of the slot 20.. Disposed on the periphery of the heads 33, there is provided two stops 36 and 31 united by an inclined wall 38. Adjacent theheads 33, the housing I0 is provided with. two restricted bores 39 opening into the counterbores I9 ahead of the center axis of the shaft 23. Within these restricted bores, there is: slidably mounted a plunger 40 maintained. in engagement with the stops 36 or 31 by the tension. of a compression spring M. The ends of the plungers 40 protruding from the bores 39 are formed. with a bevel 42, capable of engagement with the inclined wall 38.

When. the retainer is positioned as illustrated in. Fig. 1, the yoke throat 30 protrudes sumciently within the counterbore P5 to prevent the passage of the collar l4. The retainer 29 is held in that position by the engagement of the spring pressed plunger 40 with the stop 36, maintaining the yoke throat 30 in engagement with the housing II] or wall 22 of the slot 20, and the arms 3i and 32 in engagement with the ribs I1. It will be seen that the complete lower wall of the retainer 29 is held in engagement with the front housing It), thus the accidental blows transmitted by the collar [4 to the yoke throat 30 are checked by the housing' I0 and distributed thereto on more thanv one'half of its periphery, preventing thereby the breakage of the retainer or of the housing and afiording an efficient tool arresting device.

If it is desired to withdraw the tool I3 from the housing H), the handle 35 may" be rotated downwardly or in a counter-clockwise direction to position the retainer as illustrated in Fig. 2.

In this position, the yokenthroat. 30 is out of the counterbore I5, and consequently out of possible engagement with. the collar I4, allowing thereby the removal of the cutting tool l3. The retainer 29 is maintained in the opened position by the engagement of the spring pressed plunger 40 or more specifically by the engagement of its bevel 42 with the inclined wall38 of the retainer. a

When the retainer 29 islocated in a closed position as illustrated inFig. 1, the cutting tool may be introduced in themachine without manipulating the tool retainer. The collar I4 will engage the lower wall of the yoke throat 30 and will raise the same'sufilciently to allow the passage of the collar and consequently permit the introduction of the cutting tool. The yoke throat 30 will not be raised suiiiciently to permit the engagement of the plungers 40 with the inclined walls 38, thus the retainer after the passage of the collar, will snap back to a closed position by the tension of the spring pressed plungers 30 on the stops .0.

The shaft 23 may be removed from the aperture l8 by inserting a nail or any similar member through the orifice 28 and move the plunger 25 rearwardly against the compression of the spring 27. When the plunger is out of engagement with the recess 24, the shaft 23 may be removed from the aperture l8.

Although the foregoing description is necessarily of a detailed character, in order to completely set forth the invention, it is to be understood that the specific terminology is not intended to be restrictive or confining and it is to be further understood that various rearrangements of parts and modification of structural detail may be resorted to without departing from the scope or spirit of the invention as herein claimed. 7 a

I claim:

1. A tool retainer comprising a housing formed with a bore adapted to slidably receive the shank of a cutting tool, a collar formed integral on said shank, a counterbore within said housing within which said collar is free to slide, a single opening leading from one side of said housing into said counterbore, a shaft within said housing diametrically opposed to said opening, a yoke retainer pivotally mounted upon said shaft formed with a closed end portion movable through said opening into or out of engageable position with said collar, and a handle integral with said retainer by which said closed end portion may be moved into or out of engagement with said collar, said handle and retainer falling short of the outer ends of said housing irrespective of the position of said portion with respect to said collar.

2. A tool retainer comprising a housing having a collared cutting tool slidably mounted therein, a yoke retainer formed with a throat movable into or out of engagement with the collar of said cutting tool to prevent or permit the removal of the latter from said housing, the throat of said yoke having arms extending therefrom pivotally secured to said housing, and means integral with said housing engageable with'saidthroat andsaid arms for limiting the pivotal movement of said yoke retainer toward the frontend of said housing when said throat is in engageable position with the collar of said tool.

3. A tool retainer comprising a housing formed with a bore adapted to slidably receive the shank of a cutting tool, a counterbore within said housing adapted to slidably receive a collar integral-with said tool formed thereon at a convenient distance from the end of said shank, a yoke retainer having arms extending from the closed end thereof to the exteriorof said house ing for pivotal engagement therewith, and a transversally disposed slot within the side wall of said housingopening within said counterbore through which the closed end of said yoke is pivotally movable into or out of said counterbore to prevent or permit the removal ,of said tool from said housing.

4. A tool retainercomprising a housing formed with a bore adapted to slidably receive the shank of a cutting tool, a counterbore within said housing adapted to slidably receive a collar integral with said tool formed thereon at a convenient distance from the end of said shank, a transversally disposedslot within the wall of said housing openingwithin said counterbore, a yoke retainer formed with a throat having arms extending therefrom to the exterior of said housing for pivotal engagement therewith at a point substantially diametrically opposed to said slot, said throat being pivotally movable within said slot into; or out of engagement with said collar, the movement of said throat within said slot being limited by the walls of said slot.

5. A tool retainer comprising a housing formed with a bore adapted to slidably receive the shank of acutting tool, a, counterbore within saidhousing adapted to slidably receive a collar integral with said tool formed thereon at a convenient distance from the end of the shank, a shaft withing said housing, a yoke retainer comprising a throat having arms extending therefrom pivotally mounted on the ends of said shaft, a slot within said housing opening into said counterbore, said throat being pivotally movable through said slot into or out of engaging position with said collar to prevent or permit the removal of said cutting tool from said housing, a recess intermediate the ends of said shaft, and a spring actuated plungerengageable with the side walls of said recess to prevent the removal of said shaft from said housing.

6. A tool retainer comprising a housing having a collared cutting tool slidably mounted therein, a' yoke retainer having the closed ends thereof movable into or out of engaging position with the collar of said tool to prevent or permit the removal of the latter from said housing, the open end of said yoke forming arms pivotally secured 1 to the exterior of said housing, and supporting surfaces integral with said housing disposed on more than one half of the periphery thereof, said surfaces being engageable with the closed end and arms of said yoke to limit the pivotal movement of the latter in a clockwise direction.

7. A tool retainer comprising a housing having a collared tool slidably mounted therein, a shaft within said housing, a retaining member pivotally mounted on said shaft into or out of engageable position with the collar of said tool,

said retaining member having its pivotal movement into engaging position with the collar of said tool limited by its engagement with a portion of said housing, said shaft being located above the engaging portion of said retaining member with said housing, said retaining member falling short of the outer ends of said housing irrespective of the position of the former with respect to the collar of said tool.

JOHN C. CURTIS. 

